The versatile USB-C port allows all sorts of data and power to pass across it. You can attach docks that let you expand your available ports, with spots for USB Type-A, HDMI or DisplayPort video, ethernet, and pass-through power via a USB-C power cable.
But a dock that doesn’t have an external power source—plugged in via an adapter to an AC outlet or through USB-C power pass-through—has strict limits on the power it can draw and , perhaps).